2

My problem is when I'am trying to use DHCP server to give out IP address the Ip address that it gives away is the default gateway of the DHCP server and it only gives ip address to a single PC the rest of the PC I get the error DHCP fail APIPA being used

Thanks sooo much all help will be greatly appreciated

enter image description here

Configuration for the router:

Current configuration : 2394 bytes
!
version 12.4
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname HQ
!
!
!
enable secret 5 $1$mERr$GvDaTJK9lhdXRUPWKA74O0
!
!
!
!
!
!
no ip cef
ipv6 unicast-routing
!
no ipv6 cef
!
!
!
username isp password 0 isppassword
!
!
!
!
!
!
!
!
ip ssh version 2
ip domain-name ccnars.com
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
 no ip address
 duplex auto
 speed auto
!
interface FastEthernet0/0.9
 encapsulation dot1Q 9
 ip address 172.16.1.41 255.255.255.248
!
interface FastEthernet0/0.10
 encapsulation dot1Q 10
 ip address 172.16.1.33 255.255.255.248
!
interface FastEthernet0/0.15
 encapsulation dot1Q 15
 ip address 172.16.1.17 255.255.255.240
!
interface FastEthernet0/0.20
 encapsulation dot1Q 20
 ip address 172.16.1.1 255.255.255.240
!
interface FastEthernet0/0.25
 encapsulation dot1Q 25
 ip address 172.16.0.241 255.255.255.240
!
interface FastEthernet0/0.30
 encapsulation dot1Q 30
 ip address 172.16.0.225 255.255.255.240
!
interface FastEthernet0/0.40
 encapsulation dot1Q 40
 ip address 172.16.0.193 255.255.255.224
!
interface FastEthernet0/0.45
 encapsulation dot1Q 45
 ip address 172.16.0.161 255.255.255.224
!
interface FastEthernet0/0.50
 encapsulation dot1Q 50
 ip address 172.16.0.129 255.255.255.224
!
interface FastEthernet0/0.55
 encapsulation dot1Q 55
 ip address 172.16.0.97 255.255.255.224
 ip helper-address 172.16.0.99
!
interface FastEthernet0/0.60
 encapsulation dot1Q 60
 ip address 172.16.0.65 255.255.255.224
 ip helper-address 172.16.0.99
!
interface FastEthernet0/0.65
 encapsulation dot1Q 1 native
 ip address 172.16.0.1 255.255.255.192
 ip helper-address 172.16.0.99
!
interface FastEthernet0/1
 no ip address
 duplex auto
 speed auto
 shutdown
!
interface Serial0/0/0
 no ip address
 clock rate 2000000
 shutdown
!
interface Serial0/0/1
 no ip address
 clock rate 2000000
 shutdown
!
interface Serial0/1/0
 ip address 122.49.0.129 255.255.255.224
 ipv6 address 2000:ACAD:2017:0:7A31::129/94
 ipv6 enable
!
interface Serial0/1/1
 no ip address
 clock rate 2000000
 shutdown
!
interface Vlan1
 no ip address
 shutdown
!
ip classless
ip route 0.0.0.0 0.0.0.0 122.49.0.130 
!
ip flow-export version 9
!
ipv6 route ::/0 2000:ACAD:2017:0:7A31::130
!
!
!
!
!
!
line con 0
 password password
 login
!
line aux 0
!
line vty 0 3
 login local
line vty 4
 login
!
!
!
end

Configuration for the L3 switch which is connected to the router:

Current configuration : 2126 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Switch
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/1
 switchport trunk encapsulation dot1q
 switchport mode trunk
 duplex full
 speed 100
!
interface FastEthernet0/2
 switchport trunk encapsulation dot1q
 switchport mode trunk
 duplex full
 speed 100
!
interface FastEthernet0/3
 switchport trunk encapsulation dot1q
 switchport mode trunk
 duplex full
 speed 100
!
interface FastEthernet0/4
 switchport trunk encapsulation dot1q
 switchport mode trunk
 duplex full
 speed 100
!
interface FastEthernet0/5
 duplex full
 speed 100
!
interface FastEthernet0/6
 duplex full
 speed 100
!
interface FastEthernet0/7
 duplex full
 speed 100
!
interface FastEthernet0/8
 duplex full
 speed 100
!
interface FastEthernet0/9
 duplex full
 speed 100
!
interface FastEthernet0/10
 duplex full
 speed 100
!
interface FastEthernet0/11
 duplex full
 speed 100
!
interface FastEthernet0/12
 duplex full
 speed 100
!
interface FastEthernet0/13
 duplex full
 speed 100
!
interface FastEthernet0/14
 duplex full
 speed 100
!
interface FastEthernet0/15
 duplex full
 speed 100
!
interface FastEthernet0/16
 duplex full
 speed 100
!
interface FastEthernet0/17
 duplex full
 speed 100
!
interface FastEthernet0/18
 duplex full
 speed 100
!
interface FastEthernet0/19
 duplex full
 speed 100
!
interface FastEthernet0/20
 duplex full
 speed 100
!
interface FastEthernet0/21
 duplex full
 speed 100
!
interface FastEthernet0/22
 duplex full
 speed 100
!
interface FastEthernet0/23
 duplex full
 speed 100
!
interface FastEthernet0/24
 duplex full
 speed 100
!
interface GigabitEthernet0/1
 switchport trunk encapsulation dot1q
 switchport mode trunk
!
interface GigabitEthernet0/2
!
interface Vlan1
 no ip address
 shutdown
!
interface Vlan50
 mac-address 0090.0cb3.9901
 ip address 172.16.0.132 255.255.255.224
!
ip default-gateway 172.16.0.129
ip classless
!
ip flow-export version 9
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
 login
!
!
!
end

configuration for the L3 switch in the middle of the L2 switches:

Building configuration...

Current configuration : 2065 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Switch
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/1
 switchport trunk encapsulation dot1q
 switchport mode trunk
 duplex full
 speed 100
!
interface FastEthernet0/2
 switchport trunk encapsulation dot1q
 switchport mode trunk
 duplex full
 speed 100
!
interface FastEthernet0/3
 switchport trunk encapsulation dot1q
 switchport mode trunk
 duplex full
 speed 100
!
interface FastEthernet0/4
 switchport trunk encapsulation dot1q
 switchport mode trunk
 duplex full
 speed 100
!
interface FastEthernet0/5
 duplex full
 speed 100
!
interface FastEthernet0/6
 duplex full
 speed 100
!
interface FastEthernet0/7
 duplex full
 speed 100
!
interface FastEthernet0/8
 duplex full
 speed 100
!
interface FastEthernet0/9
 duplex full
 speed 100
!
interface FastEthernet0/10
 duplex full
 speed 100
!
interface FastEthernet0/11
 duplex full
 speed 100
!
interface FastEthernet0/12
 duplex full
 speed 100
!
interface FastEthernet0/13
 duplex full
 speed 100
!
interface FastEthernet0/14
 duplex full
 speed 100
!
interface FastEthernet0/15
 duplex full
 speed 100
!
interface FastEthernet0/16
 duplex full
 speed 100
!
interface FastEthernet0/17
 duplex full
 speed 100
!
interface FastEthernet0/18
 duplex full
 speed 100
!
interface FastEthernet0/19
 duplex full
 speed 100
!
interface FastEthernet0/20
 duplex full
 speed 100
!
interface FastEthernet0/21
 duplex full
 speed 100
!
interface FastEthernet0/22
 duplex full
 speed 100
!
interface FastEthernet0/23
 duplex full
 speed 100
!
interface FastEthernet0/24
 duplex full
 speed 100
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
!
interface Vlan1
 no ip address
 shutdown
!
interface Vlan50
 mac-address 0001.647d.b301
 ip address 172.16.0.132 255.255.255.224
!
ip default-gateway 172.16.0.129
ip classless
!
ip flow-export version 9
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
 login
!
!
!
end

Configuration for the L2 switch:

urrent configuration : 2999 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Switch
!
!
!
!
!
spanning-tree mode pvst
!
interface FastEthernet0/1
 switchport mode trunk
 duplex full
 speed 100
!
interface FastEthernet0/2
 switchport access vlan 65
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/3
 switchport access vlan 60
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/4
 switchport access vlan 60
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/5
 switchport access vlan 50
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/6
 switchport access vlan 50
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/7
 switchport access vlan 45
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/8
 switchport access vlan 45
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/9
 switchport access vlan 40
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/10
 switchport access vlan 40
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/11
 switchport access vlan 30
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/12
 switchport access vlan 30
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/13
 switchport access vlan 25
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/14
 switchport access vlan 25
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/15
 switchport access vlan 20
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/16
 switchport access vlan 20
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/17
 switchport access vlan 15
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/18
 switchport access vlan 15
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/19
 switchport access vlan 10
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/20
 switchport access vlan 10
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/21
 switchport access vlan 9
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/22
 switchport access vlan 9
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/23
 switchport access vlan 55
 switchport mode access
 duplex full
 speed 100
!
interface FastEthernet0/24
 switchport access vlan 55
 switchport mode access
 duplex full
 speed 100
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
!
interface Vlan1
 no ip address
 shutdown
!
interface Vlan50
 mac-address 00d0.ba6d.a901
 ip address 172.16.0.129 255.255.255.224
!
interface Vlan65
 mac-address 00d0.ba6d.a902
 no ip address
!
ip default-gateway 172.16.0.129
!
!
!
!
line con 0
!
line vty 0 4
 login
line vty 5 15
 login
!
!
!
end
  • What VLAN is the DHCP server on? Have you configured your scopes correctly? – Ron Trunk Aug 30 '17 at 17:04
  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you can provide and accept your own answer. – Ron Maupin Feb 19 '18 at 18:20
4

It appears that some of your ports are in VLANs that do not have ip helper addresses on the router. They won't get addresses from your server.

2

On the dhcp side just verify your scopes are correct.

Make sure you can ping the dhcp server that is in your ip helper command from the switches. I have seen where ip helper was in place but the network the dhcp was on wasn't routed properly.

Verify your vlan interfaces that are gateways have ip helper addresses pointing to the right server/servers.

If that is all correct do some troubleshooting with Wireshark.

To see what servers are replying run Wireshark with a filter, capture the traffic and do release renew your address so it request an address.

  1. Plug the computer into the network. Wait for the interface to be active. Depending on spanning tree it could be close to a min.

  2. Start Wireshark and choose the right interface.

  3. Release RENEW your ip address. On windows open a command prompt and run this command.

This will do both release and renew.

Ipconfig /release & & Ipconfig /renew
  1. After about 30 to 60 seconds stop the Wireshark capture and in the filter window put a filter in to see dhcp traffic.

I use...

bootp.option.type == 53

You can also use this but it doesn't show all dhcp and bootp like the above filter...

udp port 68 or port 67

These captures will show what is responding. You may do this process several times to see if it looks like incorrect servers are responding. Sometimes you'll see no responses if there is an issue or more than one if you have a configuration error, a rogue dhcp server or if you run two dhcp servers (maybe half the scope on one server and the other half on another as a form of redundancy. In that case the first one to respond "wins" but you will most likely see them both respond).

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